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Biomedical subjects

S Sawada

Publications and source records attributed to S Sawada.

At least 631 records · Page 35Linked to original sources
PubMedDate not supplied

Percutaneous internal fistulization of a lung abscess after incomplete external drainage.

Internal drainage was performed with expandable metallic stents in a 79-year-old male with lung abscess secondary to bronchogenic carcinoma. Initial external drainage was prolonged, and internalization of drainage allowed removal of the external drainage catheter. Connection of abscess cavity to obstructed bronchus was created after passing a steerable guidewire percutaneously through the abscess into the bronchus. This new type of internal drainage technique may be applicable to patients with prolonged standard percutaneous external drainage of lung abscesses.

Aged↗
PubMedDate not supplied

Expandable metallic stent treatment for malignant colorectal strictures.

Four patients were treated by placement of an expandable metallic stent (two Gianturco Z-stents, two Ultraflex stents) for malignant colorectal strictures. All four patients were able to defecate after stent placement. Stent migration was recognized in one patient. Two patients suffered from tenesmus after stent placement.

Aged↗
PubMedDate not supplied

Relative biological effectiveness and dose rate effect of tritiated water on chromosomes in human lymphocytes and bone marrow cells.

Tritiated water (HTO) is a major toxic effluent from the nuclear power industry, that is released into the environment in large quantities. The low dose radiation effect and dose rate effect of HTO on human lymphocytes and bone marrow cells have not been well studied. The present study was therefore undertaken to investigate the HTO dose-response relationship for chromosomal aberrations in human lymphocytes and bone marrow cells at low in vitro radiation doses ranging from 0.1 to 1 Gy. Lymphocytes (G0 stage) and bone marrow cells were incubated for 10-150 min with HTO at a dose rate of 2 cGy/min (555 MBq/ml). The relative biological effectiveness (RBE) of HTO was calculated with respect to 60Co gamma-rays for the induction of dicentric and centric ring chromosomes at low radiation doses. The RBE value for HTO beta-rays relative to 60Co gamma-rays was 2.7 for lymphocytes and 3.1 for chromatid aberrations in bone marrow cells. Lymphocytes were also chronically exposed to HTO for 6.7-80 h at dose rates of 0.5 cGy/min (138.5 MBq/ml) and 0.02 cGy/min (5.6 MBq/ml). There was a 71.5% decrease in the yield of dicentrics and centric rings at the dose rate of 0.02 cGy/min, indicating a clear dose rate effect of HTO. The RBE value for HTO relative to 137Cs gamma-rays was 2.0 at a dose rate of 0.02 cGy/min, suggesting that low HTO dose rates produce no increase of the RBE values and that the values may be constant between 2 and 3 within these dose rates. These results should prove useful in assessment of the health risk for humans exposed to low levels of HTO.

Bone Marrow↗
PubMedDate not supplied

Fibroma of the vulva.

We describe a patient with fibroma of the vulva. The tumor had areas of marked hypointensity consistent with fibrosis on T1 and T2 weighted magnetic resonance (MR) images. The presence of abundant fibrous tissues on MR images enabled us to make a preoperative diagnosis of fibroma.

Adipose Tissue↗
PubMedDate not supplied

Squamous cell carcinoma arising in a mature teratoma with metastasis to the urinary bladder.

We describe a patient with squamous cell carcinoma arising in a mature teratoma. Magnetic resonance (MR) images revealed a solid lobulated mass attached to the ovarian cyst containing a fat-fluid level. The solid component with extension into pelvic fat showed as hypointensity on T2-weighted MR images with good enhancement. A metastatic tumor to the urinary bladder was also demonstrated.

Carcinoma, Squamous Cell↗
PubMedDate not supplied

Multiple myeloma: short T2 on MR imaging.

We describe a rare case of multiple myeloma with marked hypointense areas on both T1- and T2-weighted images. Amyloid deposition and calcification were not found histologically. Hypointensity on T2-weighted images may be caused by distributed free radicals produced by significant macrophages.

Back Pain↗
PubMedDate not supplied

An improvement of the Ames test using a modified human liver S9 preparation.

INTRODUCTION: In preliminary studies on the Ames test using human liver S9 fractions, we found that the crude human S9 fractions, obtained following centrifugation of the tissue homogenate for 20 min at 9000 x g, were not always sterile. When this was the case, the S9 fractions were often accompanied by an increased number of colonies above the normal range on plates in the solvent control used in the Ames test. In addition, we also sometimes identified the incorporation of a small amount of fat in the crude human liver S9 fractions. We have therefore obtained a purified fat-free S9 fraction by a simple modification to the crude S9 preparation; fat was completely removed by centrifugation of the crude S9 fraction. METHODS: Using the purified and crude human S9 fractions (two lots each), both the sterility and the number of bacterial colonies produced on a plate with five bacterial tester strains by solvent controls (purified water and dimethyl sulfoxide) were examined. The findings were then compared to those observed with phosphate buffer or S9 fraction from rats pretreated with phenobarbital/5,6-benzoflavone. RESULTS: The data show that each of the crude human S9 fractions was not sterile and produced an increasing number of colonies with each solvent control, almost equal to the sum of the numbers of contaminating bacterial colonies and spontaneous revertant colonies observed with phosphate buffer or the rat S9 fraction. On the other hand, both the purified human S9 fractions were sterile, and the number of colonies that appeared in each solvent control was similar to that of spontaneous revertant colonies observed with phosphate buffer or the rat S9 fraction. DISCUSSION: These results indicate that this new procedure of S9 preparation, modified with an additional recentrifugation step, may provide a high quality of purified fat- and bacteria-free S9 fraction for use in the Ames test.

Biotransformation↗
PubMedDate not supplied

Interobserver and interstudy variability of myocardial blood flow and flow-reserve measurements with nitrogen 13 ammonia-labeled positron emission tomography.

BACKGROUND: Experimental studies have shown that positron emission tomography (PET) with 13N-labeled ammonia provides accurate quantification of regional myocardial blood flow (MBF) under rest and stress conditions. To establish the clinical utility of this method, the interobserver variability and the temporal variability of serial measurements of blood flow and coronary flow reserve (CFR) must be known. This study investigated the interobserver and temporal reproducibility of 13N-labeled PET for measurement of MBF and CFR. METHODS AND RESULTS: Initial and follow-up 13N-labeled ammonia PET studies were performed at rest and during adenosine infusion in six normal volunteers and six patients with stable coronary artery disease. Two investigators analyzed dynamically acquired data from the initial studies and one investigator analyzed the follow-up studies. Time-activity curves of tissue tracer activity were derived by a semiautomated sampling routine. A three-compartment model and curve-fitting algorithm were used to determine estimates of MBF in five myocardial regions. The interobserver correlations for MBF and CFR were excellent (r = 0.96 and 0.93, respectively). The interstudy correlation was good for rest and stress MBF (r = 0.87). The estimates of CFR on the initial and follow-up studies demonstrated a fair correlation (r = 0.72). For individual myocardial regions, there was considerable interstudy variability of stress MBF and CFR, with a mean percent difference for CFR of 19% +/- 19% in normal volunteers and 38% +/- 16% in patients with coronary disease. In normal subjects, regional CFR was highly reproducible (95%) when the values were defined as either normal (> or = 2.5) or reduced (< 2.5). CONCLUSIONS: The interobserver of reproducibility of 13N-labeled ammonia PET estimates of regional MBF was excellent. The temporal reproducibility of MBF and CFR was fair, with individual regions demonstrating substantial interstudy variability.

Adult↗
PubMedDate not supplied

A randomized clinical trial of radiation therapy versus thermoradiotherapy in stage IIIB cervical carcinoma.

To clarify the role of thermoradiotherapy for FIGO Stage IIIB cervical carcinomas, both the clinical response and survival of patients treated with radio- or thermoradiotherapy were investigated. Forty patients with Stage IIIB uterine cervix carcinoma were treated with external beam irradiation to the pelvis, combined with iridium 192 high-dose-rate intracavitary brachytherapy. All patients were divided randomly into the following two groups: the radiotherapy (RT) group of 20 patients, who underwent radiotherapy alone; and the thermoradiotherapy (TRT) group of 20 patients, who underwent three sessions of hyperthermia in addition to radiotherapy. The primary endpoint of this study was local complete response and survival. A complete response was achieved in 50% (10 of 20) in the RT group versus 80% (16 of 20) in the TRT group (p = 0.048). The 3-year overall survival and disease-free survival of the patients who were treated with TRT (58.2 and 63.6%) were better than those of the patients treated with RT (48.1 and 45%), but these differences were not significant. The 3-year local relapse-free survival of the patients who were treated with TRT (79.7%) was significantly better than that of the patients treated with RT (48.5%) (p = 0.048). TRT, as delivered in this trial, was well tolerated and did not significantly add to either the relevant clinical acute or long-term toxicity over radiation alone. TRT resulted in a better treatment response and 3-year local relapse-free survival rate than RT for patients with FIGO Stage IIIB cervical carcinoma.

Aged↗
PubMedDate not supplied

Random number generation evaluation in patients with systemic lupus erythematosus indicates a heterogeneous nature of central nervous system vulnerability.

OBJECTIVE: To evaluate the vulnerability of the central nervous system (CNS) in patients with systemic lupus erythematosus (SLE). METHODS: Forty-eight patients with SLE, 58 with schizophrenia in remission and 39 healthy controls were enrolled in the study. Patients vocally generated 100 numbers in a random fashion, using numbers 0 to 9, and were evaluated with seriality scores. Patients with SLE were subgrouped according to differences in the presence of Raynaud's phenomenon, anti-phospholipid antibody, lupus activity, and a history of neuropsychiatric (NP) lupus, and these patients were also evaluated by comparison with their counterparts. RESULTS: In general, patients with SLE showed lower seriality scores than patients with schizophrenia, and higher seriality scores than normal controls. The scores of the patients with a history of NP lupus matched those with schizophrenia, and the scores of never having NP lupus matched those of the healthy controls. CONCLUSIONS: CNS vulnerability may be prolonged in patients who have a history of NP lupus even when they appear to be in normal NP status. The damage in random number generation (RNG) observed in patients with a history of NP lupus seemed equal to that found in those with schizophrenia, whereas those patients never having NP lupus appeared to be equal to the controls. The current study suggests a heterogeneous nature of SLE and prolonged damage, especially in CNS vulnerability, when evaluating with RNG.

Adult↗
PubMedDate not supplied

Can the clearance of tumor necrosis factor alpha and interleukin 6 be enhanced using an albumin dialysate hemodiafiltration system?

Patients with acute hepatic failure (AHF) have elevated levels of inflammatory cytokines such as tumor necrosis factor alpha (TNF-alpha) and interleukin 6 (IL-6). Recently, we have shown selective hemodiafiltration with albumin dialysis, as an extracorporeal liver support device (ECLVS), to be effective in the clearance of multiple toxins that are elevated in AHF. Our objective was to evaluate whether ECLVS would be effective in the clearance of TNF-alpha and IL-6. An in vitro continuous hemodiafiltration circuit was used with single pass counter-current dialysis. A known amount of recombinant rat TNF-alpha and IL-6 was added to heparinized bovine blood and filtered across a polyalkyl sulfone hemofilter using matched filtration and dialysate flow rates. During 4 hours, the serial TNF-alpha and IL-6 concentrations were measured in the circulating blood, and the content of each cytokine was calculated using mass balance. For each cytokine, clearance was determined for two dialysate groups at constant temperature and pH (group 1: dialysate = 0.9 normal saline, n = 5; group 2: dialysate = albumin 2 gm/dl, n = 5). Analysis of data was performed using ANOVA and Student's t-test. There was improved clearance of TNF-alpha and IL-6 when albumin was used in the dialysate (81+/-0.09% of the initial TNF-alpha and 77+/-0.04% of the IL-6 quantities) compared with when 0.9 normal saline was used as the dialysate (58+/-0.14% of the initial TNF-alpha and 56+/-0.18% of the IL-6 quantities); p < 0.03. An ECLVS utilizing hemodiafiltration with albumin dialysis is more effective than conventional hemofiltration in the clearance of TNF-alpha and IL-6 and, therefore, may benefit patients with acute hepatic failure.

Albumins↗
PubMedDate not supplied

Use of the placenta as an artificial lung.

Oxygen transfer across a single cotyledon of the human placenta was assessed by using three different perfusates in the maternal circuit: 1) M-199 culture medium, 2) human adult red blood cells (RBCs), and 3) perflubron. These maternal circuit perfusates were oxygenated with a membrane oxygenator. RBCs were perfused on the fetal side of the circuit and samples were taken preplacenta and postplacenta for each maternal perfusate. PO2 and PCO2 were measured and O2 transfer was calculated for each maternal perfusate. O2 transfer per single cotyledon (mean +/- SE) was 0.18 +/- 0.04, 0.20 +/- 0.03, and 0.15 +/- 0.05 ccO2/min when using: 1) M-199, 2) RBCs, and 3) perflubron, respectively. O2 transfer per kilogram of placental tissue was 13.08 +/- 2.78, 14.57 +/- 2.05, and 10.43 +/- 3.79 ccO2/kg per minute when using: 1) M-199, 2) RBCs, and 3) perflubron, respectively. When extrapolated to the individual weights of the entire placenta, the O2 transfer was 9.15 +/- 1.95, 10.20 +/- 1.43, and 7.30 +/- 2.65 when using: 1) M-199, 2) RBCs, and 3) perflubron, respectively. We conclude from these data that O2 transfer can be accomplished during placental perfusion. Larger studies are required to differentiate efficacy among the three maternal circuit perfusates.

Adult↗
PubMedDate not supplied

CT demonstration of portal vein remnant within metastatic liver tumor.

We describe a patient with a metastatic liver tumor that showed a cordlike shadow traversing the tumor on CT. Histopathologically, this cordlike shadow within the metastatic liver tumor was proved to be an infiltrated portal vein without blood flow surrounded by fibrous tissue. Vascular structures traversing a focal lesion may be seen not only in focal fatty infiltration or lymphoma but also in metastatic liver tumor.

Adenocarcinoma↗
PubMedDate not supplied

Five year prospective study on blood pressure and maximal oxygen uptake.

1. The relationship between physical fitness (maximal oxygen uptake VO2max) and incidence of hypertension was investigated through a prospective study for a total of 16,525 human-years of observation. 2. This study involved 3305 Japanese males whose blood pressure (BP) was normal when they received their first physical examination before the age of 50. They were monitored from 1983 to 1988. The BP of 425 subjects was diagnosed as hypertension in the fifth year. 3. Fitness levels were divided into quintiles according to VO2max levels, and were compared with the changes of BP and relative risk of hypertension after adjustment for age, initial percentage of body fat (PFAT), initial BP, alcohol consumption, cigarette smoking status and familial history of hypertension. The increase in BP of subjects in the least fit group was higher than in any other group. Relative risk was calculated using a multiple logistic regression and was 1.9 x higher in the least fit group compared with the fittest group. 4. The subjects were classified into three groups: the improved VO2max group, the deteriorated VO2max group and the unchanged VO2max group. The increase in BP of the improved VO2max group was significantly lower than the other two groups after adjustment for changes in PFAT, age, initial PFAT, initial BP, fitness level, alcohol consumption, cigarette smoking status and familial history of hypertension. 5. It is concluded that low VO2max level is related to higher incidence of hypertension. An improved VO2max would therefore be able to prevent hypertension.

Adult↗
PubMedDate not supplied

Calibration of Mg2SiO4(Tb) thermoluminescent dosimeters for use in determining diagnostic x-ray doses to adult health study participants.

Characteristics of Mg2SiO4(Tb) thermoluminescent dosimeters (TLD) were ascertained preparatory to measuring doses from diagnostic x-ray examinations received by Adult Health Study participants. These detectors are small, relatively sensitive to low-dose x-rays, and are appropriate for precise dosimetry. Extensive calibration is necessary for precisely determining doses according to their thermoluminescent intensities. Their sensitivities were investigated by dose, according to x-ray tube voltage, and by exposure direction, to obtain directional dependence. Dosimeter sensitivity lessened due to the fading effect and diminution of the planchet. However, these adverse effects can be avoided by storing the dosimeters at least 1.5 h and by using fresh silver-plated planchets. Thus the TLDs, for which sensitivities were determined in this study, will be useful in subsequent diagnostic x-ray dosimetry.

Adult↗
PubMedDate not supplied

Intrahepatic metastasis by orthotopic implantation of a fragment of murine hepatoma and its related molecules.

Intrahepatic metastasis is a major modality in the recurrence of hepatoma. Establishment of the intrahepatic metastasis model would be useful for evaluating new anticancer therapies and analyzing the molecular mechanisms of tumor metastasis. Orthotopic implantation of a fragment of CBO140C12 hepatoma into the liver resulted in the formation of a solitary tumor nodule and its intrahepatic metastasis. In contrast, implantation of ADras3 cancer cells did not show any metastasis on day 21. CBO140C12 cells showed enhancement of the invasive, adhesive and migratory capabilities, as compared with ADras3 cells. Furthermore, mRNA expression and gelatinolytic activity of MMP-9 were detected in CBO140C12 cells, and the expression of mRNA for MT1-MMP in CBO140C12 cells was greater than that in ADras3 cells. Thus, intrahepatic metastasis of CBO140C12 tumor might be involved in the enhancement of the invasiveness of tumor cells via marked expression of MMP-9 and MT1-MMP.

Animals↗